Brake



IDec. 29, 1931. v. BENDlx ET AL BRAKE Filed Aug. l, 1928 l 'PatentedDec. 29, 1931y UNITED STATES Pari-:NT` OFFICE VINCENT BENDIX, OFCHICAGO, ILLINOIS, ,ANDLUDGER E. LA. BRIE, F SOUTH BENID,

INDIANA, ASSIGNORS T0 BENDIX BRAKE COMPANY, OF\SOUTB BEND, INDIANA, A.

CORPORATION OF ILLINOIS BRAKE Application led. August 1,

This invention relates to brakes, and is illustrated as embodied in aninternal expand,- ing brake for an automobile. A11 object of theinvention is to provide a very powerful brake, preferably in bothforward and reversel directions of operation, without undue complicationand in a manner permltting economical manufacture.

-of the invention, including various'noveland j bodiment. shown in theaccompanying draw.

ln one desirable arrangement, there is a floating device, shown asincluding a pair of pivotally-connectedshoes, and which is arranged toVanchor at one end when the drum is turning in one directionand at theother end when the drum is turning in the other direction. r1`hisdevice, according to an important feature of the invention, is op.-eratedby a novel .servo shoe acting through simpliied connections suchas pivoted levers, engaged by opposite ends of the servo shoe and havinga camming action on opposite ends of the floating friction device. Theservo shoe, and the connections through which it operates, yalso embodysubstantial novelty of construction in and of themselves.-

The above and othery objects and vfeatures desirable details ofconstruction and arrangement, will beapparent from the emings, in which:s

' Figure l is a vertical section through the brake, just inside the headof the brake drum, and showing the brake shoes in side elevation; Figure2 isa radial section through the servo shoev and operating meanstherefor taken on the line'2-2 of Figure 1;

Figure 3 is a radial section on the line 3-3 of Figure `1, showing oneof the devices -through L which the servo shoe operates the mainfriction means.

Figure 4 is a section through-the ioating pivot taken on the line 4-4 ofFigure 1; and

Figure 5 is a section on the line 5?-5 of` AFigure 1 showing the'stopfor determinin the idle position of the-brake shoes. y rlhe illustratedbrake includes adrotatable brake drum 1 0, at the open side of which isa'suitable support such as a backing plate /12,

and within which is the brake friction means.

192s. serial no. 296,754.

may be provided for determining the positions of the shoes when thebrake is released.

Between the upper endsl of shoes L14 and 16 is arranged a servo shoe 24,shown with spaced parallel webs 26 between which is a hardened stampedU-section thrust plate 28 engaged by a roller .30 mounted on aneccentric portion at the end of a brake camshaft.

32 journaled in a bracket 34 carried b the backing plate 12. Turningshaft 32 orces the servo shoe 24 against the drum, against theresistance of return springs 36, to'apply the brake, whereupon the servoshoe tends to turn in one direction or the other with the drum.

Atits opposite ends, the servo shoe 24 is connected by means such aspivots 38 to applying devices such as levers 40 mounted on fixed ulcrums42 carried by the backing plate 12. Pivots 38 may pass through slots ornotches in the outer ends of levers 40, so that the shoe 24 is not atanytime pulled away from the drum bythe levers. Shoes 14 and 16 areformed at their upper ends with rounded recesses within which roundedportions ofthe inner ends of levers 40 are adapted to t,`which portionsthus serve as part of the. anchoring means to transmit the brakyingtorque to oneor the other of the fulcrums or posts 42. U

The shoe' ends may be reinforced by steel plates or stampings 44projection-welded to theirA opposite sides. The shoes 14'and 16 arenormally held in released positions by return springsj46, thesespringsand springs 36 all bemg shown attached to a stamping 48 secured to thebacking plate 12. Fulcrums or anchor posts-42 are shown provided withwashers 50 to confine the shoe ends laterally.

The lower ends of the shoes may also be reinforced by plates 52projection-welded to their sides; pivot 18 having washers 54 coniningthe shoe ends laterally;

In operation if the drum is turning clockwise, when shoe 24 engages thedrum, shoe 24 nroves' to the right and operates lever 40 with a cammingaction to force shoe 16 away from its anchorage to complete theapplication ofthe brake, shoe 14 remaining anchored against its lever40, which is turningy drum, a floating friction device within thel drum,a floating servo shoe arranged between the ends of the device, and twoapplying devices, one connected to `each en'd of the servo shoe andAacting -on the corresponding end of the friction device'one serving asan anchor when the drum is turning in one direction and the other as ananchor when the drum is rotating in the other direction.y

2. A brake comprising, in combination, a drum, a friction device withinthe drum, a floating servo shoe arranged between the ends of the device,and two applying devices, one connected to each end of the servo shoeand acting on the corresponding end of the friction device, saidfriction device anchoring against one or the other of the applyingdevices according to the direction of drum rotation.

3. A brake comprising,in combination, a l

drum, a floating friction device within the drum, a floating servo shoearranged between said ends of the device, and applying levers pivotedrespectively to the opposite ends of the servo shoe and acting on thecorresponding ends of the friction device and serving as anchors for thefriction device.

4. A brake comprising, in combination, a drum, a floating frictiondevice within the drum, a floating servo shoe arranged between the endsof the device, and two applying devices, one connected to each end ofthe servo shoe adapted to act on the corresponding end of the frictiondevice and to serve as an anchor therefor, together with an applyingdevice acting on the servo shoe between said two applying devices at theends of the servo shoe.

5. A brake comprising, in combination, a drum, a floating frictiondevice within the drum, a floating servo shoe arranged between the endsof the device, and applying levers pivoted respectively to the oppositeends of the servo shoe adapted to act on the. corresponding ends of thefriction device and -to serve as anchors therefor, togetherwith anapplying device acting on the servo shoe between said two applyinglevers at the ends -of the servo shoe.

Y friction device, a lever pivoted at one end andhaving between its endsa camming engagement with the friction device, and a servo shoe pivotedto the other end of said lever, said pivoted end of the lever beingarranged to take the torque of the friction device.

9. A brake comprising, in combination, il. friction device,a leverpivoted at one end and having between its ends a camming engagement withthe friction device, and a servo shoe acting on the other end of saidlever, said pivoted end of the lever being arranged to take the torqueof the friction device.

10. A brake shoe comprising spaced webs, with a U-section thrust membersecured between said webs facing inwardly.

In testimony whereof, we have hereunto signed our names.

` VINCENT BENDIX.

LUDGER E. LA BRIE.

